1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/fault-inject.h>
3 #include <linux/slab.h>
4 #include <linux/mm.h>
5 #include "slab.h"
6
7 static struct {
8 struct fault_attr attr;
9 bool ignore_gfp_reclaim;
10 bool cache_filter;
11 } failslab = {
12 .attr = FAULT_ATTR_INITIALIZER,
13 .ignore_gfp_reclaim = true,
14 .cache_filter = false,
15 };
16
__should_failslab(struct kmem_cache * s,gfp_t gfpflags)17 bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags)
18 {
19 /* No fault-injection for bootstrap cache */
20 if (unlikely(s == kmem_cache))
21 return false;
22
23 if (gfpflags & __GFP_NOFAIL)
24 return false;
25
26 if (failslab.ignore_gfp_reclaim &&
27 (gfpflags & __GFP_DIRECT_RECLAIM))
28 return false;
29
30 if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB))
31 return false;
32
33 return should_fail(&failslab.attr, s->object_size);
34 }
35
setup_failslab(char * str)36 static int __init setup_failslab(char *str)
37 {
38 return setup_fault_attr(&failslab.attr, str);
39 }
40 __setup("failslab=", setup_failslab);
41
42 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
failslab_debugfs_init(void)43 static int __init failslab_debugfs_init(void)
44 {
45 struct dentry *dir;
46 umode_t mode = S_IFREG | 0600;
47
48 dir = fault_create_debugfs_attr("failslab", NULL, &failslab.attr);
49 if (IS_ERR(dir))
50 return PTR_ERR(dir);
51
52 debugfs_create_bool("ignore-gfp-wait", mode, dir,
53 &failslab.ignore_gfp_reclaim);
54 debugfs_create_bool("cache-filter", mode, dir,
55 &failslab.cache_filter);
56
57 return 0;
58 }
59
60 late_initcall(failslab_debugfs_init);
61
62 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
63